Hygrometer



H. Y. NORWOOD E1 AL HYGROMETER Dec; 4, 1934.

Filed June 6, 1932 INVENTOR v Harry. K Nora/00d Everett E Newell BY AT ORN Patented Dec. 4, 1934 HYGROMETER Harry Y. Norwood, Rush, and Everett E. Ne well,

Rochester, N. 1., assignors to Taylor Instrument companies, Ro e tion of New York N. Y., a corpora- Applicationlune 6, 1932, Serial No. 615,528

2 Claims.

The invention relates to hygrometers. In hygrometers of one type, it has been the practice to utilize the expansion and contraction along one, dimension only of a hygroscopic element formed of any one of several materials such as hair, strips of paper, wood and the like, to give an indication of the prevailing relative humidity. Where such change in one dimension only of the material is relied upon to give an' indication of moisture conditions, the resulting instrument has necessarily been relatively bulky as well as comparatively complicated and expensive to manufacture.

In-accordance with the present invention, it is proposed to provide a device which utilizes the resultant of thecombined changes in two dimensions of a hy ro opic member, to give an indication of the existing relative humidity. This and other-features of the invention will appear from the detailed description and claims,

' when taken with the drawing in which Fig. 1 is a side elevation of a hygrometer of the present invention with certain parts thereof broken away; and Fig. 2 is a side elevation of the hygroscopic element showing the manner in which it is mounted.

In'the drawing, 5 designates a support or anyor moisture which it absorbs or-gives off. However, a suitable hygroscopic member may con sistot a piece or wood in the form of a disc with cate its movement, but as herein shown, the free end of the band 11 is connected through an adiustable link 12 to the end of the segment ar arm 13. This arm is pivoted at 14 and its free end is provided with a segment gear 15 which engages a ear 16 fixed on a rotatable arbor 17., There is mounted on the arbor 1'7, an indicator 18 which swings over the graduated scale on the dial 21, a fragment of which only is shown. A hair spring, the detailed mounting of which is not illustrated, tends to move the indicator 18 clockwise as the material of the disc expands. While it is not essential to the invention, it is preferred to protect both faces of the disc 6'by perforated plates 20, also mounted on bolt '1, which plates are slightly separated from the respective faces of washers.

the by-means of forms wherein the resultant of the changes in two dimensions is utilized to give an indication of changing moisture conditions.

We claim:

1. In a device of the class described, a member of hygroscopic material fixed against rotation,

said member having arelatively large cross-sectional area, a flexible element connected at one end tosaid member and enga in a portion of the periphery thereof, and indicating'means ar- 2. In a device ofthe class described, a hygroscopic member having a substantial cross-sectional area, a flexible strip having one end fl'xed, said strip being wrapped about a substantial portion of the perimeter of said area, and an indieating member strip.

actuated by free end of said ranged to be actuatediay the movement of the free end of said element. 

